DALLAS -- The UFC's summer schedule currently lists a grudge match between bitter rivals, Chael Sonnen and Wanderlei Silva, as the headliner of a UFC Fight Night card in Brazil on May 31.

However, at least for the moment, the pairing between the two TUF Brazil 3 coaches appears to be wishful thinking more than a set-in-stone date.

"Yeah," White affirmed when asked on Thursday if the fight still has yet to be signed. "There's a lot more to that story than (I can say).

"This is a frustrating job. S--t happens to me every day. ... It'll get done. We'll get it done."

White refused to reveal the specific hurdle that is preventing UFC officials from finalizing the match-up, although he did state that it had nothing to do with Sonnen's usage of testosterone replacement therapy (TRT), or the Nevada State Athletic Commission's recent decision to ban the controversial treatment.

"I haven't heard otherwise," White said. "One of the things about Chael Sonnen is he's a very good communicator. So if Chael felt that something was in jeopardy or something wasn't happening, he would let us know."

Sonnen, a known user of TRT, recently stated that the ban could potentially force him to exit the sport.

Regardless, White downplayed the American's comments, stating that the hold-up was coming from Silva's side, although he could not identify why.

"He's not balking," White said of Silva. "Not even a little bit. It's not over money either. I can't tell you. It has to do with the show (TUF Brazil 3). It has to do with the show, that's all I can tell you.